A wiki is any type of web site where inability to edit the contents is the exception rather than the rule. Exceptions are usually made either for certain types of edit (wikispam), for certain users who consistently violate the site's editorial policy, or for certain pages which tend to attract vandalism.
The term "wiki" is also obliquely used to refer to a collaborative philosophy ("the wiki way") with a very flat social hierarchy, where users gain the consensual authority for any controversial actions through informal dialogue with their collaborative peers.
- List of wikis: Wikipedia, Appropedia, Citizendium, Conservapedia, KeyWiki, Issuepedia, RationalWiki, Akvopedia
- The success of wiki-based communities with very little in the way of central governance has been described as The Wisdom of Crowds or collective wisdom